Even undiagnosed siblings of children with autism tend to struggle with anxiety, depression and social difficulties.

Theory of mind difficulties are likely to be more central to autism than to attention deficit hyperactive disorder, whereas executive function problems are more often associated with the latter.

A new behavioral test in zebrafish may help researchers zero in on the biology of social interactions.

Boosting the levels of the chemical messenger serotonin makes mice that model autism more social — and brings new hope to a shelved theory in autism.

In May, the U.S. Food and Drug Administration guaranteed an experimental autism drug a speedy review for approval, but some scientists are skeptical of the drug’s potential.

Teenagers in the general population who have trouble with social communication are at double the risk of purposefully harming themselves with suicidal intentions than their peers.

Mice with a mutation in a top autism gene may have altered levels of certain gut bacteria; feeding the mice one of these bacterial species eases some of their troubles.

Two new parent questionnaires could help clinicians identify autism in babies and in members of racial or ethnic minority groups.

The latest manual of international disease codes is out, a franchise claims to have an autism cure, and two reports diverge on the validity of the social-motivation hypothesis.

People with mutations in SHANK3 have milder features than do those missing a chunk of DNA that includes the gene.